Getting my feet wet (CNC wise)

[Pherdie]

Another recent posting by Jackery about his Stepperhead finally pushed me over the edge into the world of CNC (my compliments to Alan on his incredible machine I might add). So I ordered up a couple of CNC books that were recommended on a past thread to get some foundational knowledge. They have yet to arrive.

I do have a well equipped manual shop with good fundamental knowledge in the use of same, as well as good electronic skills and test equipment, computer skills, including Basic/Fortran programming ability and a late model laptop to dedicate to any CNC project. Unfortunately, I do not have ANY knowledge of CNC software.

I thought it might be a good beginners project to couple my 8" rotary turntable and/or my semi-universal dividing head to a stepper and control it with my laptop. I realize there is a dedicated controller available (Division Master) with a CNC interface, or a dedicated programmable controller, something like a STAMP, but I was wondering if there is a basic CNC control program that could be used in lieu (4th axis?) and at the same time teach me CNC program use? Maybe something I can continue to use as I move up to a homemade CNC machine?

[John Stevenson]

Yes you could use Mach 3.

http://www.machsupport.com/

It's a free download with a license cost of $179 if I remember.
The demo version works fine but is limited to 500 lines of code before it stops which should be fine to run a rotab and get your feet wet.

Shout up if you get stuck.

[Pherdie]

Thanks for the response, John! I've seen that mentioned often.

I'll give that a try.......

[MaxHeadRoom]

There is also a freebe at cncsimulator.com
Max.

[George_Race]

As the guys above suggest, Mach3 is a good place to start. Very versatile program.
You are also going to need a program to convert drawings to GCode. Give CamBam a try. The program will fully function for 40 runs before you have to buy it.
George

[JEZX]

mach3 is easy to use , laptops will not run stuff well (from the lil i know) you may look for a new old computer

[Gadget]

I use LinuxCNC formerly known as EMC2 and am very happy with it. It is free and is downloaded with the Ubuntu Linux 10.4 OS and LinuxCNC pre-installed. You can even run it from a CD for testing purposes but you can't save any configuration that way.

[Pherdie]

Thanks for all the input (and yes, I did find out a laptop is not ideal for the purpose). I obtained a copy of Mach3 and went through most of the basic intro videos; a lot to digest in a short period of time.

It would seem to me that in order to drive a rotary table the easiest way would be to scale the representative axis such that the DRO "distance" displayed will be 360.000 units (in either .in or cm) when the rotary table has made one full revolution. Specific partial rotation increments (as in gear tooth cutting) can either be accomplished by stepped G code line execution or manual axis value inputs. Does this seem reasonable or am I missing something? Please be patient, I'm floundering here, this is all new..........

[John Stevenson]

Fred,
Read this recent post, explains all.

http://bbs.homeshopmachinist.net/showthread.php?t=53976

[macona]

Ditch the laptop. Just use an old PC.

[Pherdie]

Ah, so there is direct indexing support. Makes perfect sense. I should have done a more exhaustive search before my posting, so my apologies to all for asking the same question again.

With my table ratio of 90:1 and a 200 step stepper, that's about .02 deg./step which should work well. I have yet to fire Mach3 back up and look at the angular function but I assume there is a function to relate rotation to other axis travel so eventually I can corner the market on Quorn motor posts.

So happiness on that level but being severly spatially challenged in the shop really turns me off to the use of a desktop, even though I have Ethernet and a wireless access point in the shop. Ergonomically, the use of an iPad would really seem ideal (wireless connect to an interfacing controller?)......

Again, thanks to all who responded.

Fred

[John Stevenson]

Ergonomically, the use of an iPad would really seem ideal (wireless connect to an interfacing controller?)......

Again, thanks to all who responded.

Fred

And some one ring the wireless front doorbell or opens the garage door down the road and you end up with 37 1/2 teeth on a gear. :D

[toolsrul]

I've been using a lap top to run my 4 axis CNC Taig on Deskcnc w/servos & never had a problem.

[djc]

I've been using a lap top to run my 4 axis CNC Taig on Deskcnc w/servos & never had a problem.

That's because DeskCNC has dedicated motion control hardware on its own board. All the laptop does in your case is to drip feed the Gcode the the board.

[Jaakko Fagerlund]

That's because DeskCNC has dedicated motion control hardware on its own board. All the laptop does in your case is to drip feed the Gcode the the board.
You can use the same kind of hardware with Mach3 also, there is plenty of options for USB connected motion controllers that have a plugin for Mach3.